SmogRank / History / City race
Cities in United States, worst air first, day by day
Each measured city's average over the 30 days to every day since January 2023, worst first. Find your own city to follow it through the race, or keep to one country.
The worst cities in United States for PM2.5 over the 30 days to 21 May 2023: Port Isabel 17.6 µg/m³, Miles City 17.5 µg/m³ and Great Falls 15.1 µg/m³.
- 1Port IsabelTexas17.6
- 2Miles CityMontana17.5
- 3Great FallsMontana15.1
- 4TexarkanaTexas14.7
- 5West FargoNorth Dakota14.7
- 6Columbia FallsMontana14.4
- 7HobbsNew Mexico14.3
- 8Los AngelesCalifornia13.6
- 9PierreSouth Dakota13.4
- 10New HollandPennsylvania13.3
- 11Rapid CitySouth Dakota13.0
- 12EdinburgTexas12.7
- 13ParadiseCalifornia12.7
- 14LaredoTexas12.5
- 15Beaver FallsPennsylvania12.5
- 16Coconut CreekFlorida12.3
- 17ScottsbluffNebraska12.3
- 18HighlandsTexas12.2
- 19Lacy-LakeviewTexas12.2
- 20Jurupa ValleyCalifornia12.1
+ 675 more cities, 11.9 µg/m³ and below
Not counted on this day, too few days measured: Anthony since 15 May 2023, Augusta since 30 Mar 2023, Chalmette since 30 Mar 2023 and 3 more cities. Days missing from the source archive fall in this window, so fewer countries are counted.
Cities counted each day
A city's number is its average over the 30 days, shown only when 21 of them were measured (5 of 7 on the 7-day race), the same minimum as the 30- and 7-day boards. A city whose monitors go quiet fades out where it stood rather than sliding down, so a gap never reads as cleaner air. Some large countries are thin or missing because their monitors' licences don't allow reuse. How we rank.
Not covered: the government monitoring networks of China and Turkey, which publish only on their own websites; we are building the readers for them. Most cities there are missing from this board, not clean. Why.